The purpose of this study is to find a mathematical approach that allows one to shorten the electrophoresis time required for DNA sequencing. The algorithms to be developed are to calculate, on the basis of the mobilities and an estimate of the degree of band spreading (dispersion coefficient) of the two most slowly migrating components, the time required for the complete resolution of any mixture of molecules by electrophoresis. Accordingly, the minimal migration path length and corresponding position of the detector in a gel can be mathematically defined at a given field strength, ionic strength, and temperature.